Body area network facilitated authentication or payment authorization

ABSTRACT

Disclosed are examples of a method, a wearable device and a system enabling authentication of a user of a payment account or completion of a purchase transaction via signals generated by the wearable device. A process may include a wearable device generating a modulated signal using an encryption algorithm. The modulated signal may contain authentication information related to the wearable device including a cryptographic authentication message. The modulated signal is output to a biological medium interface of the wearable device that is coupled to a biological medium of a wearer of the wearable device. The biological medium is operable to conduct the modulated signal. A receiving device processes including decrypting and demodulating the modulated signal received from the biological medium. Using the demodulated signal, the authentication information transmitted from the wearable device is obtained. Based on the obtained authentication information, a transaction may be authorized, or a user authenticated.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/514,978, entitled “BODY AREA NETWORK FACILITATED AUTHENTICATION ORPAYMENT AUTHORIZATION” filed on Jul. 17, 2019. The contents of theaforementioned application are incorporated herein by reference in theirentirety.

BACKGROUND

Wireless communication devices are becoming the prevalent devices forperforming transactions and identifying a user. The ease with which aportable device or mobile device can establish a wireless connectionwhile in a user's pants pocket, jacket pocket, or purse enables a userto enter buildings, perform transactions and authenticate themselves tosystems without having to actually contact an interface.

However, the increased use of wireless communication devices, also drawsthe attention of less scrupulous persons who develop their own wirelessdevices to intercept the wireless communications to either stealidentifying information or, perhaps, decrypt the signals for use togenerate false signals that may be used to manipulate a wirelesstransaction system.

A supposed advantage of some wireless communication systems, likenear-field communication (NFC), is their relatively short range, such as5 centimeters. However, there have been descriptions of devices capableof intercepting the exchange of NFC signals from as far away as 60centimeters. In addition, devices that utilize NFC communication requirea user to take out an NFC-equipped payment card or NFC-equipped mobiledevice to complete the transaction or authentication. Touchpads alsohave difficulty because they often require a resistance or capacitancereading.

To combat eavesdropping hardware and software developers have resortedto different forms of biometrics, such as fingerprint detection, facialrecognition or voice recognition. The use of biometrics, in particular,fingerprint technology effectively eliminates any chance of asurreptitious interception of an authentication signal because thefingerprint is used as the authentication means and also eliminates theneed for a user to remove a device from their pocket or purse. However,even fingerprint readers may be exploited by thieves, for example, thereare devices configured to overlay on a fingerprint scanner and copy ofthe user's fingerprint for later use by the thieves.

Transaction and authentication system developers continually innovate tomaintain an advantage over those who aim to steal money and information.However, the less scrupulous persons also continue to innovate for waysto thwart the increased security devices and procedures. There is a needfor a more secure system for completing transactions and authenticatingidentities.

SUMMARY

Disclosed is an example of a method including a step of determining,based on receipt of a control signal, that an authentication signal isrequired to authorize a transaction. In response to the determinationthat the authentication signal is required, a wearable device maygenerate a modulated signal using an encryption or digital signingalgorithm. The modulated signal may contain authentication informationrelated to the wearable device including a cryptographic token relatedto the encryption or digital signing algorithm. The modulated signal isoutput to a biological medium interface of the wearable device. Thebiological medium interface is coupled to a biological medium of awearer of the wearable device, and the biological medium is operable toconduct the modulated signal. A receiving device receives the modulatedsignal. The modulated signal is demodulated. Using the demodulatedsignal, the authentication information including the cryptographic tokenrelated to the wearable device is obtained. Based on the obtainedauthentication information, the transaction is authorized. An indicationthat the transaction has been authorized is provided.

Also disclosed is an example of a wearable device. The wearable devicemay include a logic circuit, a memory, a modulated signal generator, anda biological medium interface. The logic circuit includes an inputinterface and is operable to perform functions. The memory is operableto store authentication information. The logic circuit, the memory, andthe modulated signal generator are coupled to one another. Thebiological medium interface is coupled to the modulated signalgenerator. Functions the logic circuit is operable to perform, includefunctions to, in response to an input received via the input interface,generate an authentication control signal. The logic circuit is alsooperable to forward the authentication control signal to the modulatedsignal generator. The modulated signal generator is operable to generatean authentication signal in response to the authentication controlsignal received from the logic circuit. The authentication signal is amodulated signal containing an encrypted message. The authenticationsignal is output from the biological medium interface to a biologicalmedium of a wearer of the wearable device. The biological mediuminterface of the wearable device is substantially in physical contactwith the biological medium of the wearer.

A system is disclosed including a wearable device and a signal detector.The wearable device includes a logic circuit, a wearable devicecommunication interface, a memory, a modulated signal generator, and abiological medium interface. The logic circuit, the memory, the wearabledevice communication interface, modulated signal generator, and thebiological medium interface are communicatively coupled to one another.The signal detector includes a processor, a signal detectorcommunication interface, and an input device operable to detect signals.The modulated signal generator is operable to generate an authenticationsignal in response to a control signal received via the wearable devicecommunication interface. The authentication signal is a modulated signalcontaining an encrypted message including a cryptographic token. Themodulated signal generator outputs the authentication signal from thebiological medium interface to a biological medium of a wearer of thewearable device. The biological medium of the wearer is in physicalcontact with the biological medium interface of the wearable device. Thesignal detector is operable to receive at the input device theauthentication signal emitted via the biological medium of the wearer.The signal detector may demodulate the authentication signal to extractthe encrypted message. The encrypted message may be forwarded, via thesignal detector communication interface, for processing to authenticatethat the wearable device is associated with an authorized user of apayment card account.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of an implementation of a system forutilizing a body area network for wireless authentication and paymentauthorizations as described herein.

FIG. 2A illustrates an example of a wearable device usable in thewireless authentication and payment authorizations system disclosed inFIG. 1.

FIG. 2B illustrates a more detailed example of a wearable device usablein the wireless authentication and payment authorizations systemexamples disclosed in the FIGS. 1 and 2A.

FIG. 2C illustrates another example of a wearable device usable in thewireless authentication and payment authorizations system disclosed inFIG. 1.

FIG. 3 presents a flow chart for a process example of authenticating andauthorizing transactions implementable in the system example of FIG. 1and the wearable device examples of FIGS. 2A and 2B.

FIG. 4 illustrates an example of a computing architecture suitable forimplementing the examples illustrated in FIGS. 1-3.

DETAILED DESCRIPTION

The various examples disclose a system, devices, and techniques thatutilize a wearer's body to conduct authentication signals to a signaldetector. Since the authentication signals are conducted through thebody, any eavesdropping of the authentication signal and the respectivecontent is mitigated. Disclosed are examples that transmit anauthentication signal that are radio-frequency signals, or sonic orultrasonic signals embedded in the skin and/or tissue including bone,which are in general referred to as “a biological medium.” Theauthentication signal, whether radio-frequency, sonic or ultrasonic, maybe received by a signal detector, which may amplify and process thereceived signal.

The authentication signal may be encrypted according to examplesdescribed herein as well as examples of the encryption key generationtechniques described in U.S. patent application Ser. No. 16/205,119,filed Nov. 29, 2018, the entire contents of which is incorporated byreference herein in its entirety.

The examples described herein include wireless methods of providingauthentication information having an increased security factor of beingtransmitted via a biological medium that minimizes the possibility ofsurreptitious eavesdropping of the authentication signal. It may behelpful to describe a system implementation.

FIG. 1 illustrates an example of a system operable to execute anauthentication operation or purchase transaction using a biologicalmedium for signal transmission.

The system 100 may include a number of components. In the FIG. 1example, the system 100 includes a signal detector 110, a wearabledevice 120, and a biological medium 130. In addition, the system 100may, in more detailed examples, include a service provider 140, anetwork 188, a merchant server 103, and a mobile device 170. A user 101may be wearing or carrying the wearable device 120. The user 101 may bea user associated with a payment account which is also associated withthe wearable device 120. The service provider 140 includes a serviceprovider network 147, an authentication server 145 and data storage 149.

The user 101 may also have a mobile device 170 that is communicativelycoupled with the network 188 via a cellular/wireless link 133 and thewearable device 120. The mobile device 170 may include a mobile devicecommunication interface 176, a processor 174, a memory 172 and othercomponents (shown in other examples). The mobile device memory 172 maysecurely store authentication information 173. The mobile devicecommunication interface 176 may be coupled to one or more transmitters,receivers or transceivers, such as a cellular transceiver, one or morewireless transceivers, such as Bluetooth™, Wi-Fi, near-fieldcommunication (NFC), or the like. The mobile device 170 may communicatewith the wearable device 120 via wireless communication link 133, whichmay be a link using one of: Bluetooth, Wi-Fi, NFC, or the like. Forexample, the mobile device 170 may receive via the mobile devicecommunication interface 176 a message indicating authenticationinformation is required from a point of sale device 180. In response,the mobile device 170 may issue a control signal to the wearable devicevia the wireless communication link 133 instructing the wearable deviceto output an authentication signal. Additional details are describedbelow.

In the example of FIG. 1, the wearable device 120 includes a logiccircuit 124, a wearable device communication interface 126, a memory122, a modulated signal generator 125, and a biological medium interface127. The logic circuit 124, the memory 122, the wearable devicecommunication interface 126, modulated signal generator 125, and thebiological medium interface 127 are communicatively coupled. Thewearable device 120 may be, for example, a ring, eyeglasses, a necklace,a wristwatch or the like. The logic circuit 124 may include ademodulation component 199 that is operable to demodulate a modulatedsignal (described in more detail below) output from a biological member.In an example, the wearable device 120 may include an input interface192 that is operable to receive inputs from a user 101 (or wearer) ofthe wearable device 120.

The signal detector 110 may, for example, include a processor 112, asignal detector communication interface 116, and an input device 115operable to detect signals. In an example, the signal detector 110 maybe coupled to a point of sale device 180, a payment receipt device 182(such as a portable payment device with a touchpad and card reader orthe like), an automatic teller machine (ATM) 184, or the like.

The input device 115 may detect either sonic, ultrasonic or radiofrequency signals, and may be operable to detect an electrical signal, asonic signal or an ultrasonic signal. For example, the input device 115may include a piezo-electric transducer, a micro-electro-mechanicalmicrophone, a radio-frequency antenna, an ultrasonic transducer, or thelike and related circuitry, such as an amplifier or the like.

The network 188 may be operable to exchange data and enablecommunications to be exchanged between the various components of thesystem 100. For example, the network 188 may include at least one of: acellular network, a data network, or an enterprise network. In anexample, the network 188 may a combination of a cellular network and adata network such as the internet. The network 188 may becommunicatively coupled to the signal detector communication interface116 of the signal detector 110 and also to the mobile device 170 as wellas a merchant server 103. For example, purchase transactions between thewearable device 120, via the signal detector 110 and either the point ofsale device 180 or the payment receipt device 182, and the merchantserver 103 may be authenticated via network 188.

The authentication server 145 may also be coupled to the signal detector110 via the network 188. The authentication server 145 is operable toperform a various functions. With respect to the present example, theauthentication server 145 may receive an encrypted message sent by thesignal detector 110 via the data network. The authentication server 145may process the received encrypted message to extract authenticationinformation related to an authorized user 101 of a payment accountassociated with the wearable device 120. The authentication server mayfor example, analyze the extracted authentication information todetermine the validity of the authentication information. For example,the authentication server 145 may access a data storage 149 coupled tothe authentication server 145 to obtain information related theauthorized user of a payment account associated with the wearable device120. The authentication information may be processed, for example,decrypted or some other process, by the authentication server and thedecrypted authentication information may be compared to the obtainedinformation to confirm the validity of the information. Theauthentication server 145 may confirm, using the authenticationinformation, that the wearable device 120 is associated with anauthorized user 101 of a payment card account. In response to aconfirmation that the wearable device is associated with an authorizeduser 101 of a payment card account, the authentication server 145 maysend, via the network 188, an authorization signal authorizingcompletion of a transaction to a point of sale device 180, a paymentreceipt device 182 (which may be a mobile or portable payment receiptdevice), or an automatic teller machine 184. In the following examples,the authentication signal is a modulated radio frequency signal or amodulated ultrasonic signal.

In an example, the signal detector 110 may be coupled to the point ofsale (POS) device 180, the payment receipt device 182 or the ATM 184.For example, the signal detector 110 may be a stand-alone device locatedin proximity to the POS device 180. Whenever any user interacting withone of the point of sale device 180, the payment receipt device 182 orthe ATM 184, the respective device may emit a control signal, which maybe transmitted via the signal detector communication interface 116 overa wireless link 136. For example, the signal detector communicationinterface may include an NFC, Bluetooth, Wi-Fi, short range LTEtransmitter or the like.

The modulated signal generator 125 is operable to generate anauthentication signal which is a modulated signal generated using anencryption algorithm 121. The authentication signal, for example, maycontain authentication information 123 related to the wearable deviceincluding, for example, a cryptographic token related to the encryptionor a digital signing algorithm 121. The authentication information may,for example, further include at least one of: a payment card identifier,an account identifier, an issuer identifier, a cryptographic token, orbiometric data. For example, a cryptographic token may be included inthe encrypted message (whether transaction, or authentication onlymessage) and may be generated using any authentication protocol.Examples of a cryptographic token include digital signatures of thetransaction message, encryptions of the authentication information, aswell as two-way protocols where the wearable device 120 could sign achallenge from the service (e.g., a purchase point of sale device, anATM or the like) being authenticated.

In another example, a digital signing algorithm, such as 121, may be analgorithm that enables authentication of the wearer of the wearabledevice as an authorized user of a payment account while the wearer usestheir finger to “sign” a touchpad, touchscreen, fingerprint reader, orthe like to authorize a purchase or complete a transaction.

The authentication signal may include an encrypted message based on, orincluding part of, the authentication information. The encrypted messagemay, for example, include information usable to authenticate that thewearable device 120 is associated with a payment account of a user. Inanother example, the encrypted message may include at least one of: anencrypted payment card identifier, an encrypted account identifier, anencrypted issuer identifier, or encrypted biometric data. Theauthentication signal may be output from the biological medium interface127 to a biological medium 130 of a wearer of the wearable device 120.The biological medium interface 127 of the wearable device may besubstantially in physical contact with the biological medium 130 of thewearer. In an example, “substantially in physical contact” may be withina range of 0.0-0.5 millimeters, 1-3 millimeters, 1-5 centimeters, or thelike.

The signal detector 110 may be operable to receive at the input device115 the authentication signal emitted via the biological medium 130 ofthe wearer (e.g. user 101). The signal detector 110 via the processor112 may demodulate the authentication signal to extract the encryptedmessage. The signal detector 110 in response to extracting the message,may forward, via the signal detector communication interface 116, theencrypted message for processing to authenticate that the wearabledevice is associated with an authorized user (e.g., user 101) of apayment card account.

In a further example, the logic circuit 124 may an input interface 192.The input interface 192 may receive inputs from an input device 193. Inresponse to the received inputs, the logic circuit 124 may retrieve theauthentication information 123 stored in the memory 122. Theauthentication information 123 stored in the memory 122 may include atleast one of: a cryptographic token, a payment card number, an accountnumber, an issuer identifier, or biometric data. The logic circuit 124may use the authentication information 123 in the generation of anauthentication control signal. In an example, the authentication controlsignal may include a cryptographic authentication message that maycontain at least the cryptographic token. The cryptographicauthentication message may include other authentication informationeither in addition to, or in place of, the cryptographic token. In anexample, the authentication control signal may be provided to themodulated signal generator 125 for use in generating a modulated signalfor output.

FIG. 2A illustrates an implementation of elements of the system 100shown in FIG. 1. In the example of FIG. 2A, a wireless wearable device210 is secured to a wearer's arm 276 by a wristband 212. The wirelesswearable device 210 is operable to transmit a radio frequency signal viaa wearer's hand 275. The wireless transmit wearable device 210 may beconfigured similar to the wearable device 120 of FIG. 1 to embed a radiofrequency signal, such as embedded RF signal 230, via the wearer's hand275. The embedded RF signal 230 is received by the signal detector 204.The signal detector 204 may include an input device 203, logic circuit202 and a signal detector (SD) communication interface 205. The inputdevice 203 may, for example, have an antenna tuned to a frequency of theembedded RF signal 230 emitted from the finger 277. The finger 277 maybe touching the input device 203 or be at least within a distance lessthan distance X, where X is, for example, 1.3 centimeters, 1.0centimeter, 5 millimeters or the like. The input device 203 may receivethe embedded RF signal 230. The embedded RF signal 230 may be amodulated signal, which is described in more detail with reference toFIG. 2B below.

The input device 203 may deliver an amplified modulated signal to thelogic circuit 202. The logic circuit 202 may demodulate the modulatedsignal and extract the authentication information embedded in theembedded RF signal 230. The extracted authentication information may beforwarded to the signal detector (SD) communication interface 205. TheSD communication interface 205 may forward the signal to either a POSdevice, such as 180 of FIG. 1, to complete a purchase or to a network,such as 188, for authentication.

It may be helpful to describe the wireless wearable device 210 of FIG.2A with reference to a biological medium, such as finger. FIG. 2Billustrates an example of system that includes a wireless wearabledevice, a modulated signal detector and a biological medium. In theexample, the wireless wearable device 220 includes a logic circuit 221,a memory 222, a modulated signal generator 224 and a biological mediuminterface referred to in this example as an antenna coupling 225. Thebiological medium 235 may include bone segment 233A, bone segment 233B,bone segment 233C, tissue 240 and fingernail 237. The signal detector204 is the same as the signal detector of FIG. 2A; therefore, noadditional details related to the structure or function of the signaldetector are provided.

The modulated signal generator 224 may also function similar to themodulated signal generator 125 discussed with reference to FIG. 1.However, the modulated signal generator 224 is operable to output amodulated radio frequency signal via the antenna coupling 225 onto (orinto) the biological medium 235. The biological medium 235 may be anybody part of a wearer of the wireless wearable device 220. For example,a wearer (such as user 101 of FIG. 1) may wear the wireless wearabledevice 220 on a shoulder strap, an armband, a fanny pack, a finger (asin a ring), wrist as in FIG. 2A, or the like.

The carrier signal upon which is modulated with the authenticationinformation including the cryptographic token or with an encrypted ordigitally signed message may be any frequency that enables transmissionvia the biological medium. For example, since the biological medium issubstantially made up of water, low radio frequency carrier signals inthe example propagate through the biological medium with less loss.Alternatively, higher frequency carrier signals may be used but withmore power than the lower frequency signals and for short durations.Examples of radio frequencies that may be used include 1 kHz, 10, kHz,100 kHz, a range such as 23 kHz-1 GHz, 2.4 GHz or the like.

The modulation scheme used to generate the embedded RF signal may be anamplitude shifting keying (ASK), a frequency-shift keying (FSK), phaseshift keying (PSK), complimentary code keying (CCK), a pulse codemodulation (PCM), techniques that include amplitude shifting acrossmultiple frequencies, or the like. Alternatively, particular phase-shiftmodulation schemes such as differential PSK (DPSK) or coherent PSK(CPSK), or more specifically, Binary PSK (BPSK), Quaternary PSK (QPSK),8PSK, 16PSK, Offset Quaternary PSK (OQPSK), SOQPSK (Shaped OQPSK) may beused. Of course, the various modulation schemes may be combined toprovide a custom modulation scheme more suited for signal transmissionthrough the biological medium, such as 235 of FIGS. 2B and 2C.

For example, the data rate for providing the authentication signal maybe low, such as, for example, less than 1 kilobit per second. To providethis data rate, it may be beneficial to utilize a hybrid modulationscheme that combines a temporal modulation scheme, such as a pulse widthmodulation (PWM) scheme, or the like, with one of the above referencedphase-shift modulation or frequency-modulation schemes. In an example,the combined (temporal with PSK) modulation scheme may be utilized toprovide accurate data transmission, acceptable signal loss as the signalpasses through the biological medium, and an acceptable data rate.Alternatively, a combined modulation scheme may include a temporalmodulation scheme with one of the other modulation schemes ASK, FSK,CCK, PCM or the like.

In addition, one or more short-range wireless communication protocolsand frequencies such as near-field communication (NFC), the EMVstandard, Bluetooth or the like, and in conformance with ISO/IEC 14443,may be used in the transmission of the modulated signal.

Upon generation of the modulated signal containing the authenticationinformation, the modulated signal generator 224 may forward themodulated signal to the antenna coupling 225 for output to thebiological medium 235. The antenna coupling 225 may, for example, be anantenna that has a conductive pad (not shown) configured for maximumpower transfer of power with respect to the frequency of the modulatedsignal. The antenna coupling 225 may be within a distance E of thebiological medium 235. The distance E may be less than 1.0 centimeter,for example, 0.5 centimeters, 0.0 centimeters (i.e., essentiallytouching the biological medium 235) or the like. Alternatively, thedistance E may be a range of distances, such as 0.3-0.5 centimeters,0.0-2.0 millimeters, or the like.

The antenna coupling 225 may output the modulated radio frequency signal245 which is input to the biological medium 235. The modulated radiofrequency signal 245 is transmitted through the bone segments 233A,233B, 233C, fingernail 237 and tissue 240 including connective tissue.The embedded radio frequency signal 279 is output from the biologicalmedium for detection by the signal detector 204. As discussed withreference to other examples, the signal detector 204 may receive andprocess the embedded radio frequency signal 279 to obtain theauthentication information. The signal detector 204 may forward theauthentication information to a point of sale or another device (or tothe network).

The system 100 of FIG. 1 may also included other examples of a modulatedsignal. FIG. 2C illustrates an example in which the modulated signal isa sonic or ultrasonic signal. In the example of FIG. 2C, the wirelesswearable device 229 may include elements like those in the wirelesswearable device 220 of FIG. 2B, such as the logic circuit 221, thememory 222, the wearable device communication interface 223, themodulated signal generator 224. The biological medium 235 is the same inboth examples shown in FIGS. 2B and 2C. In the case of sonic orultrasonic signals, the above-mentioned modulation schemes may also beutilized but the output from the wireless wearable device 229, in thisexample, is a modulated sound signal (e.g., sonic or ultrasonic). Forexample, sound waves above 20 kHz are above, or nearly above, the rangeof typical human hearing and are considered “ultrasonic.” Ultrasoundexams are performed at frequencies from 10 MHz and above. Sonic soundwaves may be considered those below 20 kHz, but that may still bedifficult for humans to hear. For example, the modulated sound signal248 may be a beeping sound or the like that is not offensive to humansor animals.

Like the wireless wearable device 229, the biological medium interface226 may include be a transducer that generates modulated sound waves inresponse the modulated signal output by the modulated signal generator224. The distance between the biological medium interface 226 and thebiological medium 235 may be a distance D. The distance D may be in therange of approximately 0.0-5.0 millimeters, approximately 0.0-5.0centimeters, or the like. The biological medium interface 226 may outputthe modulated sound signal 248 for embedding on or into the biologicalmedium 235. The embedded sound signal 278 may propagate through the bonesegments 233A-C, tissue 240 including connective tissue, and fingernail237 for output to the signal detector 204. The signal detector 204 mayinclude a processor 242, a signal detector communication interface 243,and an input device 244. The input device 244 may be amicro-electro-mechanical device, a piezo-electric device, or a similardevice that outputs an electrical signal in response to detected sound.The distance between the biological medium 235 and the signal detector204 for detection of the embedded sound signal by the input device 244may be a distance less than the distance Y. The distance Y may be, forexample, approximately 1.0 centimeter, 5.0 millimeters, 2 centimeters orthe like.

The signal detector 204 may be similar to the signal detector 110 ofFIG. 1. In the example of FIG. 2C, the processor 242 may be operable toreceive the electrical signals output from the input device 244 andprocess them to perform an authentication process or assist in thecompletion of a purchase transaction.

It may be beneficial to discuss an example of a process performed by theforegoing system and a device examples to better understand theadvantages of the disclosed examples. The described process may beimplemented on a non-transitory computer readable medium or the like.FIG. 3 illustrates an example of a process for authenticating a user orassisting in the completion of a purchase request. In the process 300 ofFIG. 3, devices such as those described in the examples of FIGS. 1-2Cmay be used. For example, based on receipt of a control signal, awearable device may determine that an authentication signal is requiredto authorize a transaction, for example, by verifying or authenticatinga user (310). In response to the determination that the authenticationsignal is required, a wearable device may generate a modulated signalusing an encryption algorithm (320). For example, prior to generatingthe modulated signal by the wearable device, a menu of one or moreauthentication options may be presenting on a display device, providedby the wearable device communication interface, of the wearable device.The wearable device may receive an input, such as a touch, gesture,motion or voice input, to the wearable device and cause the presentationof one or more authentication options on the display device of thewearable device. An authentication option may be selected via anotherinput to the wearable device. The authentication information associatedwith the selected authentication option may be retrieved from a memoryof the wearable device. In the example, the selected authenticationoption utilizes a cryptographic token.

In another example, the modulated signal may contain authenticationinformation related to the wearable device including a cryptographictoken related to the encryption or digital signing algorithm. At 330, amodulation signal generator, such as 125 of FIG. 1, may output themodulated signal to a biological medium interface, such as 127 of FIG.1, of the wearable device, such as 120 of FIG. 1. In the example, thebiological medium interface may be coupled to a biological medium (e.g.,finger, shoulder, arm, leg, jaw, head or the like) of a wearer of thewearable device. As discussed, the biological medium is operable toconduct the modulated signal, for example as an embedded modulatedsignal. A received device, such as signal detector 110 including inputdevice 115, or the like, may receive the modulated signal (340). Asdiscussed with respect to the examples of FIGS. 1-2C, a processor withinthe signal detector, such as 112 of FIG. 1, may be operable todemodulate the modulated signal. Using the demodulated signal, theprocessor of the signal detector may be further operable to obtain(350), via a signal detector communication interface, such as 116, theauthentication information related to the wearable device. Theauthentication information, which may include a cryptographic token, maybe sent to an authentication server, such as 145 of FIG. 1 via thenetwork 188. Based on the obtained authentication information, thetransaction may be authorized (360). In the example, the authorizing ofthe transaction may further include authenticating a wearable device asbeing associated with a payment card presented for completion of apurchase transaction. Alternatively, the wireless wearable device may beauthenticated as being associated with a payment account. In response tothe authorization or authentication, an indication may be providedindicating that the transaction has been authorized, the user has beenauthenticated, or both (370). For example, the indication may be anauthorization signal sent, via the data network (e.g., the Internet), inresponse to a confirmation that the wearable device is associated withan authorized user of a payment card account. Depending upon the usageexample, the authorization signal may be sent to a point of sale device,a mobile payment receipt device, or an automatic teller machineauthorizing completion of a transaction. In the examples, the point ofsale device, the mobile payment receipt device, or the automatic tellermachine is coupled to the signal detector.

In an example, the indication that the transaction has been authorizedmay be presented on a display device coupled to at least one of a mobiledevice, the receiving device (e.g., signal detector 110), or thewearable device. For example, the indication may be provided to one ormore of: a point of sale device, a payment receipt device, an ATM, amobile device associated with the wireless wearable device, a merchantserver, or the like.

As mentioned in the examples of FIGS. 2A and 2B, the modulated signalmay be a modulated radio frequency signal. In this specific example, theprocess 300 and receiving the modulated signal, via the biologicalmedium at the receiving device at 340, may include specific steps ofdetecting the modulated radio frequency signal when emitted from thebiological medium of the wearer of the wearable device. The detectedmodulated radio frequency signal to a demodulation component, such as199 in FIG. 1, within the logic circuits 202 or 221.

In addition, in the example of FIGS. 2A and 2B, the signal detector whenthe receiving, via the biological medium at the receiving device, mayfurther include detecting by an antenna (within input device 203) in thereceiving device (e.g., signal detector 204) the modulated radiofrequency signal upon emission from the biological medium of the wearerof the wearable device. The detected modulated radio frequency signalmay be provided to a signal processing component.

In another example of process 300, the modulated signal may be amodulated ultrasonic signal as in the example of FIG. 2C. When themodulated signal is a modulated ultrasonic signal, the step ofreceiving, via the biological medium at the receiving device may includeadditional details. For example, in response to the modulated ultrasonicsignal, a modulated electrical signal may be generated by a transducerof the receiving device. For example, the transducer may be an inputdevice, such as 244 described above with reference to FIG. 2C. Themodulated electrical signal may be provided to a demodulation component,such as within the processor 242.

FIG. 4 illustrates an example of an exemplary computing architecture 400suitable for implementing various examples as previously described. Inone example, the computing architecture 400 may be incorporate elementsas may be typically used to implement a server or network platform, ifappropriately programmed, as part of system 100. In another example, thecomputing architecture 400 may be incorporate optional elements that maybe typically used to implement a smart digital device or a computingdevice that may be implemented as part of system 100.

The computing architecture 400 includes various common computingelements, such as one or more processors, multi-core processors,co-processors, memory units, chipsets, controllers, peripherals,interfaces, oscillators, timing devices, video cards, audio cards,multimedia input/output (I/O) components, power supplies, and so forth.The examples, however, are not limited to implementation by thecomputing architecture 400.

As shown in FIG. 4, the computing architecture 400 includes a processingunit 404, a system memory 406 and a system bus 408. The processing unit404 can be any of various commercially available processors or number ofprocessors.

The system bus 408 provides an interface for system componentsincluding, but not limited to, the system memory 406 to the processingunit 404. The system bus 408 can be any of several types of busstructures that may further interconnect to a memory bus (with orwithout a memory controller), a peripheral bus, and a local bus usingany of a variety of commercially available bus architectures. Interfaceadapters may connect to the system bus 408 via slot architecture.Example slot architectures may include without limitation AcceleratedGraphics Port (AGP), Card Bus, (Extended) Industry Standard Architecture((E)ISA), Micro Channel Architecture (MCA), NuBus, Peripheral ComponentInterconnect (Extended) (PCI(X)), PCI Express, Personal Computer MemoryCard International Association (PCMCIA), and the like.

The computing architecture 400 may include or implement various articlesof manufacture. An article of manufacture may include acomputer-readable storage medium to store logic. Examples of acomputer-readable storage medium may include any tangible media capableof storing electronic data, including volatile memory or non-volatilememory, removable or non-removable memory, erasable or non-erasablememory, writeable or re-writeable memory, and so forth. Examples oflogic may include executable computer program instructions implementedusing any suitable type of code, such as source code, compiled code,interpreted code, executable code, static code, dynamic code,object-oriented code, visual code, and the like. Examples may also be atleast partly implemented as instructions contained in or on anon-transitory computer-readable medium, which may be read and executedby one or more processors to enable performance of the operationsdescribed herein.

The system memory 406 may include various types of computer-readablestorage media in the form of one or more higher speed memory units, suchas read-only memory (ROM), random-access memory (RAM), dynamic RAM(DRAM), Double-Data-Rate DRAM (DDRAM), synchronous DRAM (SDRAM), staticRAM (SRAM), programmable ROM (PROM), erasable programmable ROM (EPROM),electrically erasable programmable ROM (EEPROM), flash memory, polymermemory such as ferroelectric polymer memory, ovonic memory, phase changeor ferroelectric memory, silicon-oxide-nitride-oxide-silicon (SONOS)memory, magnetic or optical cards, an array of devices such as RedundantArray of Independent Disks (RAID) drives, solid state memory devices(e.g., USB memory, solid state drives (SSD) and any other type ofstorage media suitable for storing information. In the illustratedexample shown in FIG. 4, the system memory 406 can include non-volatilememory 410 and/or volatile memory 412. A basic input/output system(BIOS) can be stored in the non-volatile memory 410.

The computer 402 may include various types of computer-readable storagemedia in the form of one or more lower speed memory units, including aninternal hard disk drive (HDD) 414 (or, optionally, external hard diskdrive (HDD) 413), a magnetic floppy disk drive (FDD) 416 to read from orwrite to a removable magnetic disk 418, and an optical disk drive 420 toread from or write to a removable optical disk 422 (e.g., a CD-ROM orDVD). The HDD 414 or 413, FDD 416 and optical disk drive 420 can beconnected to the system bus 408 by an HDD interface 424, an FDDinterface 426 and an optical drive interface 428, respectively. The HDDinterface 424 for external drive implementations can include at leastone or both of Universal Serial Bus (USB) and IEEE 1394 interfacetechnologies.

The drives and associated computer-readable media provide volatileand/or nonvolatile storage of data, data structures, computer-executableinstructions, and so forth. For example, a number of computer programmodules can be stored in the drives and memory 410, 412, including anoperating system 430, one or more application programs 432, otherprogram modules 434, and program data 436. In one example, the one ormore application programs 432, other program modules 434, and programdata 436 can include, for example, the various applications and/orcomponents of the computing architecture 400. At least onecomputer-readable storage medium may include instructions that, whenexecuted, cause a system to perform any of the computer-implementedmethods and processes described herein.

Optionally, when configured as a mobile device or the like, thecomputing architecture 400 may include additional devices to enable datainput and output to a user. For example, a user may enter commands andinformation into the computer 402 through one or more wire/wirelessoptional input devices, for example, a keypad 438 and a tactile inputdevice, such as a touchscreen 440. Other input devices may includemicrophones, infra-red (IR) remote controls, radio-frequency (RF) remotecontrols, game pads, stylus pens, near-field communication devices,dongles, finger print readers, gloves, graphics tablets, joysticks,keyboards, retina readers, touch screens (e.g., capacitive, resistive,etc.), trackballs, track pads, sensors, styluses, and the like. Theseand other input devices are often connected to the processing unit 404through optional interface 442 that is coupled to the system bus 408 butcan be connected by other interfaces such as a parallel port, IEEE 1394serial port, a game port, a USB port, an IR interface, and so forth.

Another optionally element may be display 444, which may be an organiclight emitting diode (OLED), light emitting display (LED), or other typeof display device, that is also connected to the system bus 408 via aninterface, such as an optional video interface 446. The display 444 maybe internal or external to the computer 402. In addition to the display444, a computer typically includes other peripheral output devices, suchas speakers, printers, and so forth which may be coupled to the systembus 408 via the optional interface 442.

The computer 402 may operate in a networked environment using logicalconnections via wire and/or wireless communications to one or moreremote computers, such as a remote computer 448. The remote computer 448can be a workstation, a server computer, a router, a personal computer,portable computer, microprocessor-based entertainment appliance, a peerdevice or other common network node, and typically includes many or allthe elements described relative to the computer 402, although, forpurposes of brevity, only a remote memory/storage device 459 isillustrated. The logical connections depicted include wire/wirelessconnectivity to a local area network (LAN) 452 and/or larger networks,for example, a wide area network (WAN) 454. Such LAN and WAN networkingenvironments are commonplace in offices and companies, and facilitateenterprise-wide computer networks, such as intranets, all of which mayconnect to a global communications network, for example, the Internet.

When used in a LAN networking environment, the computer 402 may beconnected to the LAN 452 through a wire and/or wireless communicationnetwork interface or interface 456. The interface 456 can facilitatewire and/or wireless communications to the LAN 452, which may alsoinclude a wireless access point disposed thereon for communicating withthe wireless functionality of the interface 456.

When used in a WAN networking environment, the computer 402 can includea modem 458, or is connected to a communications server on the WAN 454or has other means for establishing communications over the WAN 454,such as by way of the Internet. The modem 458, which can be internal orexternal and a wire and/or wireless device, connects to the system bus408 via the interface 442. In a networked environment, program modulesdepicted relative to the computer 402, or portions thereof, can bestored in the remote memory/storage device 459. It will be appreciatedthat the network connections shown are exemplary and other means ofestablishing a communications link between the computers can be used.

The computer 402 is operable to communicate with wired and wirelessdevices or entities using the IEEE 802 family of standards, such aswireless devices operatively disposed in wireless communication (e.g.,IEEE 802.11 over-the-air modulation techniques). This includes at leastWi-Fi (or Wireless Fidelity), WiMax, and Bluetooth™ wirelesstechnologies, near-field communication (NFC), among others. Thus, thecommunication can be a predefined structure as with a conventionalnetwork or simply an ad hoc communication between at least two devices.Wi-Fi networks use radio technologies called IEEE 802.11x (a, b, g, n,etc.) to provide secure, reliable, fast wireless connectivity. A Wi-Finetwork can be used to connect computers to each other, to the Internet,and to wire networks (which use IEEE 802.3-related media and functions).The wireless technologies may couple to the computer 402 via one or moretransceivers (not shown) within for example the interface 442 orcommunication interface 456 that facilitate the use of the Wi-Fi, WiMax,NFC, Bluetooth wireless technologies as well as others.

The various elements of the devices as previously described withreference to FIGS. 1-4 may include various hardware elements, softwareelements, or a combination of both. Examples of hardware elements mayinclude devices, logic devices, components, processors, microprocessors,circuits, processors, circuit elements (e.g., transistors, resistors,capacitors, inductors, and so forth), integrated circuits, applicationspecific integrated circuits (ASIC), programmable logic devices (PLD),digital signal processors (DSP), field programmable gate array (FPGA),memory units, logic gates, registers, semiconductor device, chips,microchips, chip sets, and so forth. Examples of software elements mayinclude software components, programs, applications, computer programs,application programs, system programs, software development programs,machine programs, operating system software, middleware, firmware,software modules, routines, subroutines, functions, methods, procedures,software interfaces, application program interfaces (API), instructionsets, computing code, computer code, code segments, computer codesegments, words, values, symbols, or any combination thereof. However,determining whether an example is implemented using hardware elementsand/or software elements may vary in accordance with any number offactors, such as desired computational rate, power levels, heattolerances, processing cycle budget, input data rates, output datarates, memory resources, data bus speeds and other design or performanceconstraints, as desired for a given implementation.

As used in this application, the terms “system” and “component” areintended to refer to a computer-related entity, either hardware, acombination of hardware and software, software, or software inexecution, examples of which are provided by the exemplary computingarchitecture 400. For example, a component can be, but is not limited tobeing, a process running on a processor, a processor, a hard disk drive,multiple storage drives (of optical and/or magnetic storage medium), anobject, an executable, a thread of execution, a program, and/or acomputer. By way of illustration, both an application running on aserver and the server can be a component. One or more components canreside within a process and/or thread of execution, and a component canbe localized on one computer and/or distributed between two or morecomputers. Further, components may be communicatively coupled to eachother by various types of communications media to coordinate operations.The coordination may involve the uni-directional or bi-directionalexchange of information. For instance, the components may communicateinformation in the form of signals communicated over the communicationsmedia. The information can be implemented as signals allocated tovarious signal lines. In such allocations, each message is a signal.Further examples, however, may alternatively employ data messages. Suchdata messages may be sent across various connections. Exemplaryconnections include parallel interfaces, serial interfaces, and businterfaces.

It will be appreciated that the exemplary devices shown in the blockdiagrams described above may represent one functionally descriptiveexample of many potential implementations. Accordingly, division,omission or inclusion of block functions depicted in the accompanyingfigures does not infer that the hardware components, circuits, softwareand/or elements for implementing these functions would be necessarily bedivided, omitted, or included in examples.

Some examples may be described using the expression “one example” or “anexample” along with their derivatives. These terms mean that aparticular feature, structure, or characteristic described in connectionwith the example is included in at least one example. The appearances ofthe phrase “in an example” in various places in the specification arenot necessarily all referring to the same example. Moreover, unlessotherwise noted the features described above are recognized to be usabletogether in any combination. Thus, any features discussed separately maybe employed in combination with each other unless it is noted that thefeatures are incompatible with each other.

With general reference to notations and nomenclature used herein, thedetailed descriptions herein may be presented in terms of programprocedures executed on a computer or network of computers. Theseprocedural descriptions and representations are used by those skilled inthe art to most effectively convey the substance of their work to othersskilled in the art.

A process is here, and generally, conceived to be a self-consistentsequence of operations leading to a desired result. These operations arethose requiring physical manipulations of physical quantities. Usually,though not necessarily, these quantities take the form of electrical,magnetic or optical signals capable of being stored, transferred,combined, compared, and otherwise manipulated. It proves convenient attimes, principally for reasons of common usage, to refer to thesesignals as bits, values, elements, symbols, characters, terms, numbers,or the like. It should be noted, however, that all of these and similarterms are to be associated with the appropriate physical quantities andare merely convenient labels applied to those quantities.

Further, the manipulations performed are often referred to in terms,such as adding or comparing, which are commonly associated with mentaloperations performed by a human operator. No such capability of a humanoperator is necessary, or desirable in most cases, in any of theoperations described herein, which form part of one or more examples.Rather, the operations are machine operations.

Examples may be described using the expression “coupled” and “connected”along with their derivatives. These terms are not necessarily intendedas synonyms for each other. For example, the terms “connected” and/or“coupled” may be used to indicate that two or more elements are indirect physical or electrical contact with each other. The term“coupled,” however, may also mean that two or more elements are not indirect contact with each other, but yet still co-operate or interactwith each other.

As used in this application, the terms “system” and “component” areintended to refer to a computer-related entity, either hardware, acombination of hardware and software, software, or software inexecution, examples of which are provided by the examples in FIGS. 1-4.For example, a component can be, but is not limited to being, a processrunning on a processor, a processor, a hard disk drive, multiple storagedrives (of optical and/or magnetic storage medium), an object, anexecutable, a thread of execution, a program, and/or a computer. By wayof illustration, both an application running on a server or processorand the server or processor can be a component. One or more componentscan reside within a process and/or thread of execution, and a componentcan be localized on one computer and/or distributed between two or morecomputers. Further, components may be communicatively coupled to eachother by various types of communications media to coordinate operations.The coordination may involve the uni-directional or bi-directionalexchange of information. For instance, the components may communicateinformation in the form of signals communicated over the communicationsmedia. The information can be implemented as signals allocated tovarious signal lines. In such allocations, each message is a signal.Further embodiments, however, may alternatively employ data messages.Such data messages may be sent across various connections. Exemplaryconnections include parallel interfaces, serial interfaces, and businterfaces.

Various examples also relate to apparatus or systems for performingthese operations. This apparatus may be specially constructed for therequired purpose and may be selectively activated or reconfigured by acomputer program stored in the computer. The procedures presented hereinare not inherently related to a particular computer or other apparatus.The structure for a variety of these machines will appear from thedescription given.

It is emphasized that the Abstract of the Disclosure is provided toallow a reader to quickly ascertain the nature of the technicaldisclosure. It is submitted with the understanding that it will not beused to interpret or limit the scope or meaning of the claims. Inaddition, in the foregoing Detailed Description, various features aregrouped together in a single example for streamlining the disclosure.This method of disclosure is not to be interpreted as reflecting anintention that the claimed examples require more features than areexpressly recited in each claim. Rather, as the following claimsreflect, inventive subject matter lies in less than all features of asingle disclosed example. Thus, the following claims are herebyincorporated into the Detailed Description, with each claim standing onits own as a separate example. In the appended claims, the terms“including” and “in which” are used as the plain-English equivalents ofthe respective terms “comprising” and “wherein,” respectively. Moreover,the terms “first,” “second,” “third,” and so forth, are used merely aslabels and are not intended to impose numerical requirements on theirobjects.

What has been described above includes examples of the disclosedarchitecture. It is, of course, not possible to describe everyconceivable combination of components and/or methodologies, but one ofordinary skill in the art may recognize that many further combinationsand permutations are possible. Accordingly, the novel architecture isintended to embrace all such alterations, modifications, and variationsthat fall within the spirit and scope of the appended claims.

What is claimed is:
 1. A wearable device, comprising: a logic circuitincluding an input interface, wherein the logic circuit is operable toexecute an encryption algorithm; a memory operable to storeauthentication information; a modulated signal generator operable togenerate a modulated electrical signal, wherein the logic circuit, thememory, and the modulated signal generator are coupled to one another;and a biological medium interface coupled to the modulated signalgenerator, wherein the logic circuit is operable to: determine based onreceipt of a control signal that an authentication signal is required toauthorize a purchase transaction; in response to the determination thatthe authentication signal is required, instruct the modulated signalgenerator to generate a modulated signal using the encryption algorithm,wherein the modulated signal contains authentication information relatedto the wearable device including a cryptographic token related to theencryption algorithm; output the modulated signal to a biological mediuminterface of the wearable device, wherein the biological mediuminterface is coupled to a biological medium of a wearer of the wearabledevice by being substantially in physical contact with the biologicalmedium of the wearer and the biological medium is operable to conductthe modulated signal; and receive, by the wearable device, in responseto the outputted modulated signal, an indication that the purchasetransaction has been authorized.
 2. The wearable device of claim 1,wherein the logic circuit is further operable to perform: in response toreceiving via the biological medium the modulated signal at a receivingdevice, generate a modulated electrical signal by a transducer of thereceiving device; provide the modulated electrical signal to ademodulation component; and extract an encrypted message including theauthentication information from a demodulated electrical signal.
 3. Thewearable device of claim 1, wherein the logic circuit is furtheroperable to perform: in response to a payment card being presented forcompletion of the transaction, authenticating that the wearable deviceis associated with a payment card, wherein the payment card is presentedfor completion of the purchase transaction.
 4. The wearable device ofclaim 1, wherein the logic circuit is further operable to perform:present the indication that the purchase transaction has been authorizedon a display device coupled to the wearable device.
 5. The wearabledevice of claim 1, further comprising: a display device coupled to theprocessor; and wherein the logic circuit is further operable to perform:prior to generating the modulated electrical signal by the wearabledevice, present a menu of one or more authentication options on thedisplay device; receive an input selecting one or more authenticationoptions on the display device; select an authentication option viaanother input; and retrieve authentication information associated withthe selected authentication option from the memory, wherein the selectedauthentication option utilizes the cryptographic token.
 6. The wearabledevice of claim 1, wherein: the authentication information furtherincludes at least one of: a payment card identifier, a payment cardnumber, an account number, an account identifier, an issuer identifier,or biometric data.
 7. The wearable device of claim 1, wherein themodulated signal generator is operable to: generate an authenticationsignal in response to an authentication control signal received from thelogic circuit, wherein the authentication signal is a modulatedultrasonic sound signal containing an encrypted message includinginformation usable to authenticate that the wearable device isassociated with a payment account; and output the authentication signalfrom the biological medium interface to a biological medium of a wearerof the wearable device to complete a purchase transaction, wherein thebiological medium interface of the wearable device is substantially inphysical contact with the biological medium of the wearer.
 8. A system,comprising: a wearable device including a logic circuit, a wearabledevice communication interface, a memory, a modulated signal generator,and a biological medium interface, wherein the logic circuit, thememory, the wearable device communication interface, modulated signalgenerator, and the biological medium interface are communicativelycoupled to one another; and a signal detector including a processor, asignal detector communication interface, and an input device operable todetect signals via a transducer, wherein the logic circuit is operableto: determine based on receipt of a control signal that anauthentication signal is required to authorize a purchase transaction;in response to the determination that the authentication signal isrequired, instruct the modulated signal generator to generate amodulated signal using an encryption algorithm, wherein the modulatedsignal contains authentication information related to the wearabledevice including a cryptographic token related to the encryptionalgorithm; output the modulated signal to a biological medium interfaceof the wearable device, wherein the biological medium interface iscoupled to a biological medium of a wearer of the wearable device bybeing substantially in physical contact with the biological medium ofthe wearer and the biological medium is operable to conduct themodulated signal; and receive, by the wearable device, in response tothe outputted modulated signal, an indication that the purchasetransaction has been authorized; wherein the signal detector is operableto: receive via the signal detector communication interface theauthentication signal emitted as a modulated electrical signal via thebiological medium of the wearer; in response to the modulated signal,generate another modulated electrical signal by the transducer of theinput device; provide the other modulated electrical signal to ademodulation component; and demodulate the modulated electrical signalto extract an encrypted message; and forward, via the signal detectorcommunication interface, the encrypted message for processing toauthenticate that the wearable device is associated with an authorizeduser of a payment card account.
 9. The system of claim 8, wherein: theencrypted message includes information usable to authenticate that thewearable device is associated with a payment account and furtherincludes at least one of: an encrypted payment card identifier, anencrypted account identifier, an encrypted issuer identifier, acryptographic token, or encrypted biometric data.
 10. The system ofclaim 8, wherein the wearable device is a ring, eyeglasses, a necklace,or a wristwatch.
 11. The system of claim 8, wherein: the signal detectoris coupled to a point of sale device, a mobile payment receipt device,or an automatic teller machine, and the input device is operable todetect an electrical, a sonic signal or an ultrasonic signal, and is apiezo-electric transducer, a micro-electro-mechanical microphone, anantenna, or an ultrasonic transducer.
 12. The system of claim 8, furthercomprises: an authentication server coupled to the signal detector viathe signal detector communication interface, wherein the authenticationserver is operable to: receive the encrypted message forwarded by thesignal detector; process the received encrypted message to extractauthentication information; confirm, using the authenticationinformation, that the wearable device is associated with an authorizeduser of a payment card account; and in response to a confirmation thatthe wearable device is associated with an authorized user of a paymentcard account, send an authorization signal to a point of sale device, amobile payment receipt device, or an automatic teller machine, whereinthe signal detector is coupled to the point of sale device, the mobilepayment receipt device, or the automatic teller machine.
 13. The systemof claim 8, wherein the wearable device is operable to communicate witha mobile device.
 14. A signal detector, comprising: a processor; aninput device coupled to the processor and operable to receive modulatedsignals and operable to generate a modulated electrical signal; and asignal detector communication interface coupled to the processor,wherein the processor is operable to: receive via the signal detectorcommunication interface an authentication signal emitted as a modulatedsignal via a biological medium of the user; in response to the modulatedsignal, generate by the input device a modulated electrical signal;provide the modulated electrical signal to a demodulation component; anddemodulate the modulated electrical signal to extract an encryptedmessage; and forward, via the signal detector communication interface,the encrypted message for processing to authenticate that theauthentication signal is associated with an authorized user of a paymentcard account.
 15. The signal detector of claim 14, wherein: the inputdevice is operable to detect an electrical, a sonic signal or anultrasonic signal, and is a piezo-electric transducer, amicro-electro-mechanical microphone, an antenna, or an ultrasonictransducer.
 16. The signal detector of claim 14, wherein: theauthentication signal contains authentication information related to awearable device including a cryptographic token related to a digitalsigning algorithm useable to authenticate that the wearable device isassociated with a payment account.
 17. The signal detector of claim 14,wherein: the input device is operable to receive signals via abiological medium, wherein the biological medium includes skin and/ortissue including bone.
 18. The signal detector of claim 14, wherein: thesignal detector communication interface is communicatively coupled to anauthentication server; and the processor is operable to: forward theencrypted message to the authentication server; and output an indicationthat a purchase transaction has been authorized.
 19. The signal detectorof claim 14, further comprising: a modulated signal generator, whereinthe signal detector communication interface is operable to transmitsignals via the modulated signal generator; and the processor isoperable to: receive an authorization signal from an authenticationserver, wherein the signal detector communication interface iscommunicatively coupled to the authentication server; and output anindication for receipt by a wearable device requesting authenticationthat a purchase transaction has been authorized.
 20. The signal detectorof claim 19, further comprising: a display device coupled to theprocessor, wherein the processor is operable to: cause the displaydevice to present the indication that the purchase transaction has beenauthorized.